Tip-perforating machine



Apri114, 1925.

y F. F'. wl'rKus TIP PERFORATINGMACHINE Fed Jan.

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'JMX/WM `punch rod, making a Patented Apr. 14, 1925.

FRANK F. WITKUS, OF NEWPORT, NEW `HAMPSHIRE.

TIP-PERFORATING MACHINE.

Application led January 12, 1923. Serial No. 612,300.

To a/Z whom t may concern.'

Be it known that I, FRANK F. WITKUS, a citizen ot' the United States, a resident of Newport, in the State of New Hampshire and Sullivan County, have invented an Im- ]n'ovement in 'Tip-Perforating Machines, of which the following is a specification.

This invention relates to machines for forming a series ot' small perforations in sheet material, particularly in the tips and other leather portions of the upper of a shoe, for ornamental purposes.

Prior to my invention, machines for this purpose, which are in practical use have consisted ot' a series of tubular punches which are variously arranged according to the design ot figure to be punched, and mounted in a plate adapted to be removably arranged in a machine which comprises a table for supporting the plate and a vertically movable head which is engaged with the plate to force the punching tubes through the leather' which is placed in position therebeneath. Machines of this type are objectionable for several reasons, principally because the punching tubes are expensive to manufacture and frequently become broken, and this ditliculty is increased when perforations of particularly small diameter are required, also, in order that the punching tubesv may make a clean cut and entirely remove the material to be cut out, it is usually necessary to provide paper and soft metal for the tubes to cut against, and if paper is employed, the cost thereof is a' substantial item, while soft metahwhen employed, dulls the cutting edges to an objectionable extent. y

The objects of my invention are to provide a form of punching die adapted for use in the machines now employed for tip-per'- forating, in which a solid punching tool, or shearing cut, may be employed, and particularly to provide means whereby punching devices of this character may be eiectively employed for the above described purpose, so that the xpense of construction may be reduced and the durability increased to an extent which will make repairs unnecessary for long periods. Other objects arel to provide a construction which Will lend itself readily to an arrangement of the punchesto form in any desired desigm-and to permit the formation of perforations of as small, or as large diameter as may be desired.

p upon the depression of a I accomplish these objects by means of the construction hereinafter described and illustrated in the accompanying drawing in which:

Fig. 1 is a `front elevation, illustrating a preferred embodiment of/my invention.

Fig. 2 is a sectional view at line a-.a of

riff 1.

view of one of the 1n the same type of machine as that now generally employed for tip-perforating, said machine comprising, as indicated in the drawing, a' table orzsupport 1, on which. the die, as a whole, is removably mounted, and a vertically movable head or plate 2, which is provided withmeans for causing the samea to make a single reciprocation,

treadle. Accordlng to my invention, I provide a die, which comprises a. bed-plate 4, of-oblong form, having a row of perforations 4, therethrough, which conform to the row of perforations which are usually formed in the rear ed e portion of an ordinary Shoe ti and al of per orations, 4l arranged in some coni ventional design, to conform to the desired arrangement of fperforations in the mid-` dle portion of the tip. hold-down plate 6, of the same shape as the plate 4, is provided, having a' serles 'of perforations corresponding to the perforations 4 and 4b, and slidably mounted on a series of guiding posts 7, one being preferably arranfred in each corner" ortion of the plate and the plate being he d in such a position that its perforations exactly register with the perforations of plate 4. Each post 7 is provided with a shoulder 8, which engages the under side of the plate 6, and also with a tubular portion 9 "which eX- tends through the plate'4 and is slidably fitted in a bushing 10, supported in the plate 4 by a flange 11 at its upper end, the flange being flush with the upper surface of the plate 4. A coiled lifting spring 12 is arranged in cach tubular portion 9, and in so with a series or cluster A clamping or the bushing 10, between the inner end thereof and an adjusting screw 14, threaded in the lower end of the bushing 10. A head plate 16 is mounted on the upper end portions of the posts 7, and a screw 18 is threaded in the upper end of each post, the head thereof engaging the plate 16 and being countersunk, so that its outer surface is iush with the upper surface of plate 16. A coiled spring 2O is provided on each post 7 between the plates 6 and 16, the strength of which is substantially greater than thatof each corresponding spring 12. The plate 16 is also provi-ded with a series of perforations corresponding to the perforations 4, 4b of plate V4, and .which are held in register therewith and a corresponding series, or gang of punching tools or rods 22 are arranged in, and closely fitted in the perforations of the plate 16, each rod belng bent over at its upper end to form a supporting head 22a, which engages the upper side of plate 16, and extending into the perforations of the clamping plate 6. A back or top plate 24 is attached that itis held in vclose contact therewith, thereby providing an abutment for the headed ends of the punching rods 22 and also the heads of the screws 18. To provide an additional yielding engaging means between the plates 6 and 16, the plate 6 is recessed from its upper side to receive the lower ends ofa pair of coiled springs 28, said springs extending through holes formed therefor in plate 16 and engaging the plate 24 at their upper ends.

A combined guiding and stop plate 30 is attached by screws 31 to each end of the plate 6, so that the adjacent surfaces of said plates 30 may slidably engage the end portions of the plates 4, 16 and 24, and said plates 30 are provided at their lower ends with inwardly projecting flanges 32 which, in the normal position of the parts, engage the under side of the plate 4 and limit the extent to which the plates 4 and 6 may be separated by the springs 12.

A series of gage pins 34 are mounted in the plates 6 and 16 similarly to the punch rods 22, and extend through corresponding apertures therein, and through the plate 4, said pins being arranged to engage the edge of a shoe tip when inserted between the plates 4 and 6, to position the tip with relation to the punching tools. To permit adjustment of pins 34 with relationvto the punches, additional rows of perforations 35 are provi-ded in the plates located at different distances from the perforations 4a. A guard plate 86 is preferably attached to the front edge of the plate 6 and extends opposite the front edge of the plate 16.

The normal position of the die is illustrated in Figs. 1 and 3, in which position by screws 25 to the plate 16, so

which is removedin head plate, clamping the springs 12 support the plate 6 at a sufcient distance from the plate 4 to permit the tip to be perforated to be readily inserted therebetween. When the tip has thus been inserted, the machine is operated to force the plunger 2 downward, causing downward pressure to be exerted on the surface ofthe top plate 24. As the combined strength of the springs 2O and 28 is made greater than the combined strength of the lifting springs 12, the plates 6 and 16 will be forced down together compressing the springs 12 until the plate 6 is engaged with the material to be punched and is pressed thereagainst under the tension of the .springs 20 and 28. The material will thus be firmly clamped between the plates 6 and 4, as shown in Fig. 4. As soon as the springs 20 and 28 begin to be compressed, on further downward movement of plate 16, the punch rods 22 will be forced completely through the plate 6 and through the material into perforations of' the plate 4 to a sufficient extent to sever the punched-out material completely from the sheet, as shown in Fig. 5, waste material,

the successive operations, beino' forced down through the perforations therein. When the plunger raised, the plates 6 and 16 will be lifted in the reverse order by the springs, the plate 6 then acting to strip the material from the punches. As the material will be firmly clamped at all points about each perforation in the base plate 4, each punch rod will have a perfect shearing action with the edges thereof, soA that the material will 'be cut as smoothly as it would be with a sharp tubular punch.

If, for any reason, it becomes necessary to renew any of the punching rods, this may be readily done by removing the top plate 24 and removing the defective rods and inserting others, and if it is desired to perforate the edge-portion of the tip only, the rods which form the conventional ligure may be removed.

I claim:

1. A perforating plate, a clamping plate and a head plate disposed thereover, one above the other in parallel relation thereto,.each plate having a series of perforations therethrough in registering relation, a series of guide posts connected to said head plate and extendingl through and slidable in said clamping an base plates, said posts having stop shoulders for engaging -the under sides of said clamping plate to limit its movement from said springs interposed between said head and clamping plates and normally holding said clamping plate against said shoulders, adjusting screws connected to said bed plate, lifting springs interposed between said screws and the die comprising a bedv lower ends of said guide posts, means to limit the extent of separation of said base and `clamping plate by said lifting-springs and punch rods mounted in the perforations 'of said head plate and extending into the perforations of said'clamping'plates.

2. A perforating die comprising a bed plate, a clamping plate and a head plate disposed thereover, one above the other in parallel relation thereto, each plate having `a series of perforations therethrough in registering relation, a series of guide posts connected to said head plate and extending through and` slidable in said clamping and base plates, said posts having sto shoulders (arranged to be engaged by sai clamping plate to limit its movement from said ea plate, clamping springs interposed between said head and clamping plates and normally holding said clamping plate against said shoulders, bushings supported in said bed plate and within which said guide posts are slidably fitted at their lower ends, adjusting screws in the lower ends of said bushings, lifting springs in said bushings4 and engaged with said screws and with the lower ends of guide posts and stop devices connected to said clamping plate and arranged to engage said base plate to limit the separation thereof bysaid lifting springs.

In testimony whereof, I have name to this specification.

FRANK F.' WITKUS.

slgned my 

